Vibrator for medical use.



PATENTED DEC. 12, 1905.

D. T.- MARSHALL. VIBRATOR FOR MEDICAL USE.

APPLICATION FILED O0T.6.1904.

UNITED sTATEs PATENT OFFIOE.

Specication of Letters Patent.

Patented Dec. 12, 1905.

Application filed October 6, 1904. Serial No. 227,430.

To all whom t may concern:

Be it known that I, DAVID TRUMBULL MAR- SHALL, a citizen of the UnitedStates of America, residing in the city of New York,.in the county andState of New York` have invented an Improved Vibrator for Medical Use,of which the following is a specification.

The object of this invention is to improve the construction of vibratorsfor medical use, to cheapen and simplify them, and to permit the use ofa small motor for the same without liability of stoppage of thevibrators action through undue pressure on the pad.

In the accompanying drawings, Figure 1 is a sectional side elevation ofmy improved device, showing a portion of motor attached. Fig. 2 is aface view of the fulcrum-collar, and Fig. 3 is a side elevation of acomplete machine drawn to a smaller scale.

As shown on the drawings, M is the motorcasing.

S is the motor-shaft, carrying a plate P at one end, fitted with a diskD, adapted to be secured thereto by a screw s. Both disk and plate areprovided with hemispherical recesses, which when placed together form asocket S' for the ball end B of the vibratorrod R, out of line with theaxis of the shaft, and thus constituting a form of crank motion.

A cylindrical casing or tube T, open at one end, is secured to themotor-casing M by screws s2 and incloses the plate and disk of themotorshaft. A slidable collar or movable fulcrum f is fitted within oneend of the tube T, being provided with a central opening o of polygonaloutline with rounded edges and also with a depending threaded shankpassing through a slot Zin the tube T. A thumb-nut N is used to tightensaid collar in the tube and secure it in its various adjusted positionstherein.

The vibrator-rod R is formed of a bar of polygonal cross-section for allor vpart its length, with which the central opening of the collar mayengage. The rod is threaded at its outer end and provided with a ball Bat its inner end. A pad or rubber P may bevv threaded on the rod R andsecured additionally by a screw si. An open-centered protective collar cmay be placed over the end of the tube T, as shown.

In assembling the device shown the collar may be placed on the rod R,after the same has been passed through the opening in the hemisphericalrecess of the disk D andthe disk then secured in place against the plateof the motor-shaft. Then the tube T is slipped over the collar and theflanged end of the tube then secured to the motor-casing. The thumbnut Ncan be attached at any time. The protecting-collar is then placed overthe end of the tube T and finally the pad or rubber P placed in positionand secured.

In operation it-will be noted that a very small radius of throw isimparted to the inner end of the vibrator-rod from the motor-shaft,While the motion of the pad may be even less, according to the positionof the fulcrum f. The pad is given an orbital motion, which may be soslight as not to be as great as the limit of elasticity of its own body.Hence no matter what pressure the operator applies it is practicallyimpossible to stop the machine, the application of pressure to thepatient, however, varying during each revolution.

I have shown my device as directly attached to the motor-casing, as thatis my preferred form of machine. However, so long as any driving-shaftis coupled to my vibrator-rod in the manner shown I consider it withinthe scope of my broad invention.

From the foregoing description it is seen that I have invented asimple,cheap,and easilymanufactured device producing effective resultsin its intended use.

I claim as my inventionl. A vibrator, comprising a casing, a revolubleshaft therein, a tube secured to the casing, a collar having a hole ofpolygonal outline, a rod of polygonal cross-section passing freelythrough the opening, said rod having a cranked connection with the shaftand passing out of the tube and carrying a pad at its end.

2. A Vibrator, comprising a casing, a revoluble shaft therein, atubesecured to the casing, a collar having a hole of polygonal outline androunded edges, a rod of polygonal cross-section passing freely throughthe opening, said rod having a cranked connection with the shaft andpassing out of the tube and carrying a pad at its end.

In testimony whereof I have signed my name to this specication in thepresence of two subscribing witnesses.

DAVID T. MARSHALL.

Witnesses:

GEORGE G. SoHoENLANK, F. WARREN WRIGHT.

IOO

